[orgostudent]

what kind of reaction is this--

cyclohexanone + H₂N-NH-Ph / catalytic H⁺

i have to draw the structure of the product from this reaction

[macman104]

Imine Formation

[orgostudent]

so the structure should have a carbon nitrogen double bond?

[macman104]

Yes.

[sjb]

Well, the initial product might have a carbon-nitrogen double bond, but it may not be the final product.

I don't think hydrazone formation really needs acidic catalysis (based on my limited experience of 1 or 2 reactions and loads of imines, but I could be wrong)

How hard are you hitting the reaction? Something else may happen...

(edit: well, as macman104 has given a link to imine formation, I may as well play my card too, and show http://en.wikipedia.org/w/index.php?title=Fischer_indole_synthesis&oldid=158175672 )

S

[macman104]

edit: well, as macman104 has given a link to imine formation, I may as well play my card too, and show http://en.wikipedia.org/w/index.php?title=Fischer_indole_synthesis&oldid=158175672

I concede .  But somehow, I have this feeling orgostudent may not have learned fischer indole synthesis.

[AWK]

Well, the initial product might have a carbon-nitrogen double bond, but it may not be the final product.

I don't think hydrazone formation really needs acidic catalysis (based on my limited experience of 1 or 2 reactions and loads of imines, but I could be wrong)

How hard are you hitting the reaction? Something else may happen...

(edit: well, as macman104 has given a link to imine formation, I may as well play my card too, and show http://en.wikipedia.org/w/index.php?title=Fischer_indole_synthesis&oldid=158175672 )

S

Rather tetrahydrocarbazole is formed

[macman104]

Yes, but the mechanism is that of the indole synthesis no?  The fact that a cyclic ketone results in the 3 ring structure doesn't change that fact does it?

[orgostudent]

how about this....

C₅H₁₀-C=N-NH-Ph + H₂O

[AWK]

how about this....

C₅H₁₀-C=N-NH-Ph + H₂O

Yes, but not in acidic media

Do you know story of discovery of this synthesis. Soon after discovery of phenylhydrazine, in Fisher lab during organic synthesis, students synthesised phenylhydrazone of pyruvic acid (CH3COCOOH). After crystallization from ethanol all except one got the needed colorless crystals of  phenylhydrazone. This (fortunate) student got deep blue powder which cannot be dissoved in water or ethanol. Fisher started conducting an investugation and found that the alcohol used for crystallization by this student was acidic (this student pures ethenol into bottle used prviously  to hydrochloric acid). And this investigated powder appeared to be the indigo.

[sjb]

Thanks AWK, I didn't know that.

Just goes to show what with all the planned stuff that goes on these days and back before all the instrumentation we take for granted in the lab, a lot of stuff was truly discovery and very intelligent people working on fundamentals.

I wonder what people like Fischer, Perkin, Sabatier etc would make of the labs, the information exchange and everything else in modern chemistry today...

Something to ponder for the weekend, perhaps.

S

[AWK]

Perkin discovered mauveine serendipitously because he did not use a pure aniline

[orgostudent]

would it better if it was

C5H10-C=N-NH-

[AWK]

would it better if it was

C5H10-C=N-NH-

This suggests one carbon atom is outside the ring
C6H10=N-NH-Ph will be better